I learned a long time ago about something Aristotle said in, like, 1045, way before the BCS or even college football. He said, "The whole is more than the sum of its parts."

We're not trying to go metaphysical here, but when it comes to college football, Aristotle could be wrong. And we're going to tell you why. (And don't write in to explain holism, of which Aristotle's "maxim" is the general principle. Why not? Because I don't care.)

There are a lot of teams -- probably 10 to 12 -- that are going into this season thinking they have a legit shot at the national title. And there probably are about 25 to 30 more that think they have a real shot at their league title.

But every one of those teams has at least one questionable unit on either offense or defense, and today, we're going to spotlight some of them.

The reason they're important is that -- Aristotle's proclamation be damned -- you can't have a title-winning offense or defense if one of the units on either side of the ball struggles.

Here's a look at the biggest unit question on both sides of the ball in each of the Big Six leagues. We'll also take a look at the biggest unit question overall in each of the other five leagues.

These teams have the talent to win their leagues -- and in some cases, challenge for the national title -- but they won't unless these questionable units come through. In other words, the whole isn't going to be more than the sum of its parts if one of the parts is faulty.

ACCOffensive group: North Carolina running backs
The buzz: Everyone knows the Tar Heels' defense is expected to be fabulous this season. That unit is the main reason some folks are saying UNC is the biggest dark horse in the ACC. But those some folks will acknowledge that the offense has to get a lot better if the Heels really are to win. RBs Shaun Draughn and Ryan Houston combined to rush for 1,280 yards and 10 TDs last season. But Houston, a short-yardage specialist, scored nine of those, and the Heels have to get more out of Draughn this season. It would help if UNC's passing attack was more potent. But it's a double-edged sword: Is the passing attack poor because the receivers are bad or is it poor because absolutely no one respects the run? Perhaps the backs will be more productive this season -- four starting offensive linemen return -- and we can find out for sure.

Defensive group: Virginia Tech linebackers
The buzz: The Hokies uncharacteristically struggled against the run last season, allowing 128.4 yards per game to finish 40th in the nation in rush defense. Only one starting linebacker returns, and junior Barquell Rivers tore a quadriceps muscle in a weightlifting session during the spring and his recovery has been slower than expected. If he's not ready by the opener, it will be an all-sophomore crew against high-powered Boise State. Lyndell Gibson played well as a reserve last season, but no other linebacker has much experience. Potentially exacerbating the issues at linebacker is that the Hokies will have three new starters in the front four. If that rebuilt line falters, a ton of pressure will be placed on the linebackers -- and they might not be able to hold up, especially if Rivers isn't 100 percent.

BIG EASTOffensive group: Connecticut wide receivers
The buzz: As long as Randy Edsall is coach, the Huskies are going to be known for their defense and a power running game. But if they want to win the Big East -- which is wide open -- this season, the passing attack needs to show some verve. QB Zach Frazer is no star, but he certainly is good enough to lead the Huskies to the league title. He needs help from his receivers. Junior Kashif Moore, who has 49 career catches, must emerge as the go-to guy. Fellow juniors Isiah Moore and Michael Smith also must become more productive. UConn's returning receivers accounted for five TD catches last season, so big jumps in production are needed.

Defensive group: Cincinnati secondary
The buzz: The Bearcats were extremely inconsistent against the pass last season, and they especially struggled down the stretch, with Connecticut, Illinois and especially Florida carving them up. Two starters return, CB Dominique Battle and SS Drew Frey. Battle had just one pick and four pass breakups last season, which are nice numbers for a backup but not a starter. The Bearcats are going back to a 4-3 after one season using a 3-4 set, and the front seven has some potential, most notably with T Derek Wolfe and LB Walter Stewart. The secondary needs to show improvement in order to hold up its end of the bargain.

BIG TENOffensive group: Iowa line
The buzz: The Hawkeyes were a middling offensive team last season, ranking 99th in rushing offense, 89th in total offense and 86th in scoring offense. But they still won 11 games because of a tough defense and an offense that usually did just enough. The bad news is both starting tackles, including star Bryan Bulaga, are gone from last season. The good news is that the skill-position players return and get a boost from RB Jewel Hampton, who missed last season with an injury. Sophomore Riley Reiff is moving from guard to tackle; he's a big-timer who will contend for All-Big Ten honors and has the look of a future All-American. If senior G Julian Vandervelde can stay healthy, he's a solid second building block. But the other spots are still in doubt. Coach Kirk Ferentz places a huge emphasis on physical line play, and he and his staff must develop a cohesive unit. The defense is going to be quite good, so if Iowa's offense is as good as last season's, the Hawkeyes again will challenge for the Big Ten. But higher goals means the line must play better.

Defensive group: Ohio State secondary
The buzz: The Buckeyes' front seven is going to be one of the best in the nation this fall. Senior CB Chimdi Chekwa should be the best corner in the league and could garner some All-America attention. The other corner will be senior Devon Torrence, who needs to be more of a playmaker this season. Both starting safeties are new, and the Buckeyes really are going to miss SS Kurt Coleman. FS Jermale Hines should be an upgrade in coverage over Anderson Russell, the man he'll replace. The new strong safety is sophomore Orhian Johnson, who has all the needed physical tools but lacks experience. Depth at safety is a bit iffy, so the Buckeyes' last line of defense definitely bears watching.

BIG 12Offensive group: Nebraska line
The buzz: Four starters return, but the line wasn't close to being a dominant unit last season and one or two of the returnees could lose their starting jobs. A lot is expected of T Jermarcus Hardrick, a JC transfer. G Keith Williams has lost weight and is in much better shape, and he and Ricky Henry could form a solid guard duo. RT Marcel Jones hasn't lived up to billing. Nebraska should win the Big 12 North regardless. But unless the line gets more physical and aggressive, that maybe it for the Huskers' titles this season.

Defensive group: Oklahoma linebackers
The buzz: Junior Travis Lewis is one of the best 'backers in the nation; he has 253 tackles, 21.5 tackles for loss, five picks, five pass breakups and two forced fumbles in his career. But the Sooners' other two starters at linebacker are going to be new guys. Coaches are high on redshirt freshman MLB Tom Wort, who tore his ACL and missed last season; oft-injured junior Austin Box is his backup. Sophomore Ronnell Lewis, who had 22 tackles as a true freshman reserve last season, also should start on the outside. Other than Box, the reserves are untested -- talented but untested. The front four should be fine and the secondary looks good, especially at safety. That leaves the linebackers. Sterling play from Travis Lewis is a given, but how are the other guys going to play?

PAC-10Offensive group: Stanford running backs
The buzz: Stanford was surprisingly good last season, mainly because of the incredible production of RB Toby Gerhart, who ran for 1,871 yards and 28 TDs on the way to finishing second in the Heisman voting. Alas, he's gone. Stanford does have sophomore QB Andrew Luck, who has a ton of talent. But he needs some help from some running backs who haven't done much. Sophomore Stepfan Taylor, who ran for 63 yards against Arizona State and 62 against USC, should get the bulk of the carries. Sophomore Tyler Gaffney, senior Jeremy Stewart and a true freshman or two also should be in the mix. No one on this roster is going to run for 1,871 yards. If Stanford can get to that total as a team, though, it's going to be fine offensively.

Defensive group: Oregon secondary
The buzz: The Ducks allowed 18 TD passes and gave up at least two in five of their final six games last season (against just four interceptions); they have to be in a less-giving mood this fall. The Ducks look to have the talent, and fall drills should be especially spirited as players look to lock down starting spots. Four players look to be in the mix at corner -- seniors Talmadge Jackson and Chad Peppars, junior Anthony Gildon and sophomore Cliff Harris, who has the highest upside. There is talent at safety, too, with John Boyett, Javes Lewis, Marvin Johnson and Eddie Pleasant, a converted linebacker. Oregon's front seven is going to be fine; it's up to the secondary to determine where Oregon finishes in the Pac-10 race -- and nationally.

SECOffensive group: Florida wide receivers
The buzz: Most of these guys were highly recruited prep stars, but none has done much at the college level. The projected go-to guy is junior Deonte Thompson, who is the only returning receiver who had more than 14 receptions last season. Thompson has 42 career catches, and if he doesn't catch at least 50 this season, the Gators could be in trouble. The other wide receivers and tight end on the roster have 24 career catches -- 24. That does not include Chris Rainey, who has moved from backup running back to (likely) starter at slot receiver; Rainey has 13 career receptions out of the backfield. There are high hopes for sophomore Omarius Hines, who might be the most physical receiver on the roster, and redshirt freshman Andre Debose, a mega-recruit who missed last season after hamstring surgery. Florida also could use a tight end to step up. One problem: There are four on the roster and each is a freshman (two redshirts and two true). The projected starter is Jordan Reed, a redshirt who was a high school quarterback.

Defensive group: Alabama secondary
The buzz: Alabama lost nine full-time defensive starters, but the front seven in the Tide's 3-4 scheme should be quite good. E Marcell Dareus led the Tide in sacks last season despite being a reserve, and LB Dont'a Hightower has "All-America" written all over him despite missing all 10 games last season with a blown-out knee. The secondary is where the Tide could struggle a bit, even with coach Nick Saban's hands-on approach with his defensive backs. SS Mark Barron is another potential All-American, giving the Tide stars at each level of the defense. But the other three spots will have new starters. Big things -- actually, huge things -- are expected from sophomore CB Dre Kirkpatrick, but first-year starting cornerbacks in leagues as deep as the SEC have a tendency to get burned a few times during a season. It's one thing for a new lineman or linebacker to get burned; it can result in a 7- or 8-yard gain. But a burned corner can mean six points for an opponent. Sophomore B.J. Scott, junior Phelon Jones (an LSU transfer) and true freshmen John Fulton and DeMarcus Milliner are others in line for a lot of playing time. All four are talented, but that's a lot of inexperienced corners. JC transfer Dequan Menzie tore his Achilles tendon in April and could end up redshirting. Alabama's best pass defense this season might be a strong pass rush -- and the Tide have the guys to provide that.

Conference USAThe group: Houston linebackers
The buzz: The Cougars' defense was -- to be kind -- pitiful last season. They gave up 226.6 rushing yards (115th nationally), 451.3 total yards (111th) and 30.1 points (95th) per game. Those were noteworthy numbers even in a league as bereft of defense as C-USA. Coach Kevin Sumlin hired Brian Stewart as his new coordinator; Stewart was a Philadelphia Eagles defensive assistant last season after serving two years as the Dallas Cowboys' coordinator. Stewart has installed a 3-4 defense in an effort to get more speed on the field, a bold move considering Houston's linebackers didn't really stand out last season. Now, instead of three linebackers on the field, there will be four. Junior Marcus McGraw has the potential to be an all-league performer, but will he get enough help? Sophomore Phillip Steward and JC transfer Sammy Brown are the other guys most under the gun to produce. Houston's offense is going to be tremendous; the Cougars again should lead the nation in passing yards, total yards and points. But if the Cougars aspire to something more than just winning C-USA (actually, that should be their goal, since they lost in the league title game last season), the defense must play better, especially the linebackers.

Mid-AmericanThe group: Temple wide receivers
The buzz: The Owls' offensive focal point is going to be sophomore RB Bernard Pierce, who -- if he's healthy -- could run for 1,800 or so yards. But for the Owls to win the league, they have to improve their passing attack. Temple threw for 146.5 yards per game last season. Part of that -- actually, a large part of that -- can be attributed to dismal quarterback play. But last season's starter, Vaughn Charlton, now is the starting tight end, and Chester Stewart is the new quarterback. The wide receivers, most notably seniors Michael Campbell and Delano Green and junior Joe Jones, need to make the most of their opportunities to take some pressure off Pierce. If the Owls' passing game is an anemic as it was last season, they will not win the league.

Mountain WestThe group: BYU offensive backfield
The buzz: The Cougars will be without QB Max Hall (who was a senior last season) and RB Harvey Unga (gone because of an honor-code violation); Unga was bidding to become just the ninth man in FBS history to have four consecutive 1,000-yard seasons. No back on BYU's roster can hope to replace Unga, so it will be a group effort from juniors J.J. Di Luigi and Bryan Kariya and sophomore Mike Hague. Quarterback is equally problematic. True freshman Jake Heaps enrolled early and went through spring drills; he was inconsistent, not surprising considering he still should've been in high school. He will duel with Riley Nelson for the starting job in fall drills. TCU and Utah look to be the class of the Mountain West; for BYU to have any shot at contention, the quarterback and the running backs have to play beyond their years. Frankly, it's easier to see BYU finishing fourth in the league than first because of the inexperience in the backfield.

Sun BeltThe group: Middle Tennessee defensive line
The buzz: Some departures and some spring injuries have left the Blue Raiders a bit questionable in the middle of the line. Senior E Jamari Lattimore is a given, but there are questions elsewhere. The secondary has a chance to be the best in the league, and the linebackers -- despite breaking in two new starters -- should be solid. But if MTSU can't keep opponents from running right up the middle, all that other defensive talent -- and all those playmakers on offense -- isn't going to matter. The health of senior Dwight Smith and junior SaCoby Carter bears watching. There is some young talent, but it's untested.

Western AthleticThe group: Boise State linebackers
The buzz: There is no bigger favorite in a league than Boise State in the WAC. The Broncos are going to win the league; the question is whether they play for bigger things. For that to happen, the linebackers are the group that must produce. All three starters return and depth is excellent. So what's the worry? None is overly physically gifted or really much of a playmaker. They're steady but that will only get you so far. Players such as Aaron Tevis, J.C. Percy, Winston Venable, Daron Mackey, Byron Hout and Derrell Acrey need to be difference-makers this season.

This and thatChicago State hired Tracy Dildy as its basketball coach last week; that was the last job vacancy this offseason. Dildy just completed his third season as an assistant at Illinois-Chicago. He also has been an assistant at UAB, Ole Miss, Auburn, Ball State and DePaul, where he was a top recruiter for then-coach Pat Kennedy. Dildy, 47, is a Chicago native, and his hiring could make things quite interesting on the recruiting trail in his hometown.

Temple unveiled a Web site -- Pierce4Heisman.com -- promoting RB Bernard Pierce for the Heisman. Pierce, a sophomore, isn't going to win the Heisman, but kudos to the school for going the extra mile to promote him. He is a big-time running back (we mentioned him earlier in this story), and the Owls' postseason appearance last season was mostly Pierce's doing.

Southern Miss announced last week that former quarterback Jeff Hammond will be an associate athletic director for advancement. Hammond, who was at the school in the early 1970s, most recently has been known as Maj. Gen. Jeff Hammond and has commanded troops in Afghanistan and Iraq. Hammond is set to retire in September and will move into a fundraising role at Southern Miss. Presumably, it will be tough to say "no" to a man like Hammond.

The hiring of Chuck Driesell as basketball coach is paying off for The Citadel. Former Wichita State guard Kenny Manigault plans to transfer and play for Driesell. Manigault is transferring home; he is a native of Charleston, S.C., where The Citadel is located. Manigault was a big scorer and solid defender at Pinewood Prep in Summerville, S.C.

Finally, we would like to take a moment to raise a glass to the first FLW College Fishing All-America team, as chosen by FLW Outdoors magazine. Twenty fishermen were selected, including two from national champion Florida (yes, there really is a national title for college fishing, though it isn't an NCAA-sanctioned sport). The name we noticed, though, is that of Auburn's Shaye Baker; he's from Reeltown, Ala., and, really, wouldn't you expect a guy from a town named Reeltown to know how to fish?

Mike Huguenin is the college sports editor for Rivals.com. He can be reached at mhuguenin@rivals.com.